Tighter official regulation of violent computer games was called for by members of the Church of England general synod last night.

In a brief debate, members queued up to condemn the availability of ultra-violent games and the relative lack of restrictions on what children can see.

The church itself has been a victim – in 2007 images of the interior of Manchester Cathedral were used without permission in the violent game Resistance: Fall of Man.

The cathedral staff secured an apology - but not the withdrawal of the game from its worldwide market.

The cathedral's dean the Very Rev Govender Rogers Govender told the synod: "Sony's response was: "What is the church worried about? It's just a game.' I had to tell them, 'It may just be a fantasy game to you, but violence is really serious on the streets of Manchester.' We eventually managed to elicit a grudging apology."

Initiating the debate, synod lay member Tom Benyon, a former Tory MP, said: "There is a bubbling sewer of gratuitously violent and sexual pornography and games all around us … I have seen [their] pernicious effect: a family member saw a so-called game and he had nightmares. The images remained with him for months."

Benyon offered to show members extracts of violent games on a compilation DVD: "Why is it acceptable, indeed lawful, to portray the killing and burning of a woman in Fatality, the sawing up of a woman in Mortal Combat, playing football with severed heads; the chainsaw killing of a man in Saw III, rape, torture and so on? I have all these terrible games collected and if anyone has the courage to watch it, please do so.

"We are in a great muddle over regulation and the cost… can be seen in the rising crime statistics year by year. To control this material by expecting parents to control their children with warnings is like King Canute's performance with his waves. This is not just a matter of conscience and morality. It's a public health and an economic issue."

The synod called on the government to review the regulatory system for advertising video games to prevent the targeting of children, offered support for carers and parents to prevent children, young people and vulnerable adults being damaged - and promised that the church would keep an eye on the games market to monitor what was being released.